<!DOCTYPE html>
<html>
    <head>
        <script src="js/vue.js"></script>
        <style>
            .circular {
                width: 100px;
                height: 100px;
                border-radius: 50%;
                background: red;
                margin-top: 20px;
                line-height: 100px;
                text-align: center;
                color: #fff;
            }

            .bounce-enter-active {
                animation: Ami 1s;
            }

            .bounce-leave-active {
                animation: Ami 1s reverse;
            }

            @keyframes Ami {
                0% {transform: scale(0); background: red;}
                20% {transform: scale(1); background: burlywood;}
                50% {transform: scale(1.5); background: blueviolet;}
                100% {transform: scale(1); background:greenyellow;}
            }
        </style>
    </head>
    <body>
        <div id="app">
            <button @click="show=!show">CSS动画 显示/隐藏对象</button>
            <transition name="bounce">
                <div class="circular" v-if="show">圆形</div>
            </transition>
        </div>
        <script>
            var vm = new Vue({
                el:'#app',
                data : {
                    show : true
                }
            });
        </script>
    </body>
</html>